Transformation method of products containing amiantus

ABSTRACT

A method for transforming a waste product containing or completely formed of amiantus comprising subjecting the waste product to several working phases and adding of components such as calcined alumina, clay and material having a given porosity so to produce a final manufactured product free of any amiantus.

BACKGROUND OF THE INVENTION

[0001] This invention is concerned with the transformation of productscontaining amiantus. More specifically, the invention is concerned witha novel method for the clearing or cleaning of amiantus and/or fortaking care of waste materials containing amiantus so as to render thesame innocuous and salubrious and to obtain materials from use in themanufacture of products, materials for the use in the construction ofbuildings and other structures or for such other uses to which

DESCRIPTION OF THE PRIOR ART

[0002] According to the prior art, there are known methods which actuateand accomplish the storage in special burrows for toxic waste.

[0003] Provision is made for the encapsulation with hydraulic and/orchemical ligands and the englobing by means of resins.

[0004] All these solutions do not actuate and accomplish the finaldisposal, but they only remove the problem temporarily because they donot destroy or modify the amiantus structure so as to render it anon-toxic structure.

BRIEF SUMMARY OF THE INVENTION

[0005] A primary purpose of the present invention is to transform theamiantus or the waste material containing amiantus to a useful productfor the production of products having an economic advantage so that thecosts for the transformation plus a profit is made while distributinguseful products.

[0006] The method according to the invention comprises several workingphases and the addition of selected components such as calcined alumina,clay and materials having a given porosity.

[0007] The invention is concerned with a unique transformation methodcombined with the added components to provide for and to permit theobtention of materials with chemical and/or physical features so as tojustify their use as building materials, as well as being the same orequivalent to other common materials used, as well as being usable forother products.

[0008] The danger of amiantus and the danger of the waste materialcontaining amiantus has been a concern since the nineteen hundredforties and also, unfortunately, there is a concern that individualsdevelop illnesses and the possibility of developing tumors which struckthose persons exposed to the waste material with amiantus or become incontact with the cited substance.

[0009] Therefore, the inventor being quite conscious of the toxicityeffect of the amiantus, asbestos and verified the connection between thetumor commencement and the casual exposure, as well as that a largenumber of States and countries have issued special laws so to preventits use, developed the method to eliminate the deleterious effects andresults.

[0010] Generally, in the various States and countries, according totheir laws and jurisprudence, there are laws which prevent the use ofamiantus or waste products containing amiantus, and this inventionproposes to overcome these problems.

[0011] Therefore, the problem for the disposal of this waste materialhas arisen in connection with the already existing materials. And,considering the big periocolosity of the substance, it is always a largenecessary expense for actuating and accomplishing the disposal.

BRIEF DESCRIOPTION OF THE DRAWINGS

[0012]FIG. 1 is a DRX graphic representation for the test of a sample ofcement and amiantus; the amiantus is present like chrysotile and it isillustrated in the first and in the fifth peak.

[0013]FIG. 2 is graphic representation of the text of a sample, alwayswith the same cited manners of “etemit” in dust with pieces larger than0.063 millimeters, that is with a grain size larger than what isproduced or provided by the invented method; also, in this analysisamiantus is present in form of chrysotile.

[0014]FIG. 3 is DRX graphic representation of the text of a sampleobtained in accordance with the teachings of the invented method,wherein 40% of eternit is mixed with 30% of calcined alumina and 30% ofclay; to this mixture, there is added 20-35% of water to the mixture ofthe first two elements and the resultant mixture is formed, dried andcooked up to a temperature of 1200° C. with the modes cited;subsequently, the last-mentioned mixture is coated and a testing takesplace with the same mode of the previous test; the test shows that theamiantus is totally absent.

[0015]FIG. 4 illustrates a table with the completion of the chemicaltest in percentage of the eternit and of the same in grain size greaterthan or equal to 0.063 millimeters.

[0016]FIG. 5 is a table illustrating the percentage of the eternitminerals expressed in weight percentage.

[0017]FIG. 6 is table with the weight percentage for the eternit samplein grain sizes greater than or equal to 0.063 millimeters; it to benoted that the amiantus is always present in a manner similar tochrysotile.

[0018]FIG. 7 illustrates a table with the minerals percentages presentin the sample subjected to the invented method; all the form isexpressed like graphics are obtained with an x-ray diffractometer on thebasis of rules WWPOS 031/99.

DETAILED DESCRIPTION OF THE INVENTION

[0019] The transformation method of products or waste materialcontaining amiantus provides for several working phases and the additionof particular substances so as to modify the intrinsic structure of thematerials to be cleared.

[0020] The working phases, with the addition at a in the convenient timeof particular substances, are necessary and sufficient to change thecondition of the waste product to render the wanted transformations soas to have mineralogical transformation take place and to produce aproduct which no longer has any of the deleterious nature of the productor amiantus structure. Moreover, each cited phase together with theaddition of the substances provided with the elements necessary for thetransformations are a sole part of the method so that thetransformations are not possible if the particular conditions are notmet.

[0021] The invented method consists essentially of nine working phaseswith the addition during the working of the elements useful for thetransformations.

[0022] The first phase is a grinding phase. The amiantus alone and/orthe waste product with amiantus will hereinafter be alone referred to as“waste products” or “undesired waste products” and according to theteachings of this invention will be any product partially or totallyincluding amiantus, and waste products are placed inside a jaw crusherso as to obtain the pieces for the subsequent tertiary crushing insidean aro mill.

[0023] This particular mill (the aro mill) is able to reduce theamiantus and the waste products to a dimension no greater than or up to0.063 millimeters.

[0024] The material going out to the mill is sent to a wind separatorregulated in such a way that those pieces of a dimension greater than0.063 millimeters are recycled in the same manner until the dimension orsize of the waste product is less than or no greater than 0.063millimeter.

[0025] Once the desired or wanted dimension of the material is obtained,it is then stored in a sealed container.

[0026] The second phase is concerned with a dosing of the waste product.The micronized amiantus or the waste with amiantus are weighed and alsothe other used components and waste products are weighed: the calcinedalumina, the clay and the materials having the given porosity. Thosematerials having the required or given porosity which are generally usedare wood flour or hazel-shell flour. This last component changes in theuse with different weight percentages based on the wood flour or thehazel-shell flour are used.

[0027] The third working phase is a mixing phase. The dosed componentsare weighed and then the waste products are placed inside acounter-rotating mixer with a vortex to reach the homogenization of themixture. In this mixing step, (or third step), nebulized water is addedin a percentage of from 20% to 35% of the total of the dry weight of thecomponents on the basis of the necessity to obtain the necessaryplasticity for the next step which is an extrusion step.

[0028] The next or fourth phase is an extrusion. In this extrusionphase, a normal extruder for the production of building goods is used.The operation inside of the extruder provides for obtaining a plasticmass that is forced through a die chaser, which results in asemi-manufactured product for use in the next working phase.

[0029] The fifth phase is a dimensioning phase. The obtained orresultant semi-manufactured product is automatically cut and dimensionedto produce a product in the wanted or desired sizes.

[0030] The sixth phase is a drying phase. The semi-manufactured productproduced upon completion of the fifth phase is dried at temperaturelower than 100° C. so that the semi-manufactured product it does notreach a consistency which requires handling without possibility ofdeformations.

[0031] The next or seventh phase is a burning phase. In the burningphase, the manufactured product is dried with a residual dampness up to1%{circumflex over ( )}, and the manufactured product is then passedthrough a furnace which reach a temperature of up to 1250° C.

[0032] The cooking cycle or burning phase takes place as follows: forthe first two hours the product reaches a temperature of up to 350° C.,and in the next two hours the product reaches a temperature up to 550°C., then in next two hours the product reaches a temperature up to 800°C., in the next three hours the product reaches a temperature up to1050° C., in the next two hours the product reaches a temperature up to1180° C. and at the end and after another four hours the product reachesa temperature 1200° C.

[0033] At the end of the burning phase after the temperature of 1200° C.is reached, the manufactured product is allowed to cool in a naturalmanner. After this manufacture transformation phase and cooling, themanufactured product is sintered in a cooking phase.

[0034] The next or eighth phase, is an inspection of the product on thebasis of the necessary requirements for the next uses. In this phase,the amiantus in its original conditions is no longer present inside themanufactured product so that the waste product is completely eliminated.

[0035] The ninth and last phase is a packaging/storing phase. Theobtained manufacture, without or free of amiantus is then packaged andstored to complete the working cycle. The materials so obtained haveinsulation and refractory features, and they can have all thecertifications required for materials which are used in building.

[0036] The invented method is consequently a very economical method tosolve the problem of the amiantus disposal definitively such that at theend of the working phases, the amiantus is no longer present any more,but what is present is only non-present toxic materials which areacceptable materials.

[0037] In the invented method, a fundamental feature is the presence, inaddition to the cooking phase that putting thermal energy realizes thetransformation, of the additional components added or put in during thedosing and mixing phases. In the various phases the quantity percent ofthe amiantus or of the waste product with amiantus is of a value or apercentage of from 30% to 40% of the dried mixture. After determiningthe quantity of the amiantus and depending on the quantity present, arefractory clay is added in quantity percent comprising up to 30% of theweight of the mixture of the clay and the amiantus. The clay issues inthe mixture have the function of sintering ligand and of oxides bearerfor transforming the crystallographic structure of the amiantus in ahighly stable form formed to the oxides of the elements which form thesame amiantus.

[0038] In the mixing phase, a material having given porosity is placedinto the mass in working so as to lighten the structure in a percentageto be varied on the basis of the desired features of the final product.

[0039] Another fundamental component is the adding to the dosing duringthe dosing phase and to the mixing, is the calcined alumina in aquantity percent of from 26% to 30% of the dried weight. The alumina,i.e. the metallic oxide contained in the alum, is to be obtained throughdifferent processes.

[0040] A known industrial process to obtain the same is LeChatelier-Löwing process wherein the bauxite, i.e. the aluminametatrihydrate, is fused at 1000-1200° C. with soda ash inside a rotarykiln and it is then lixiviated (washed or percolated with solublematter) with hot water.

[0041] The alumina trihydrate is then changed into hydroxyaluminatewhich passes in solution Al₂O₃+2NaOH+3H₂O=2Na[Al(OH₄)]. From thefiltered solution it is precipitated with carbon dioxide at 70° C. tothe aluminum at the state of pure hydroxide2Na[Al(OH₄)]÷CO₂=2Al(OH₃)+Na₂CO₃+H₂O which changes in oxide for limingat 1200° C.-1700° C.

[0042] The calcined alumina is preferred in this method, as it is thinlydivided and is extremely reactive for permitting to have final goodswith good features of loading resistance and for the high temperatures.

[0043] In order to realize the invented method, other types of aluminummay also be used but with hydroxil groups which when heated becomealloyed with the amiantus or with the waste with amiantus. This isbecause, if it is not aluminum with hydroxil groups but substances withalkaline base, the transformation of the amiantus always together withother innocuous minerals is obtained.

[0044] Of course, making the cited phases, by the final goods have avitreous structure so that it is not suitable for use at present forbuilding materials or manufacturers.

[0045] The calcined alumina, because of its unique structure, loss inhot, the hydroxil group practically contemporary with the amiantus orwaste with amiantus, the available valences of the aluminum are renderedsuch that reacting with the mineral oxide deoxidizing of the amiantusbrings to the formation of different mineralogic structures.

[0046] The diversity of the mineralogic structures is due to thecomposition of the material to be clear and to the minimum percentagevariability of the elements put in the dosing or/and in the mixing.

[0047] The transformation method in fact changes the amiantus or wastewith amiantus in other non-toxic minerals like mullite, faialite,ghelenite, corundum, hematite, cordierite and wollastonie.

[0048] So having materials to be used for manufactures is not harmful.

[0049] The variability of the obtained products or articles ofmanufacture is due to the type of amiantus or waste with amiantus and tothe minimum variability of the components used in the doxing and in themixing. The amiantus in fact is a mineral belonging to the anphibole(i.e. calcium silicates and magnesium silicates) or to the serpentine(magnesium silicate) and it presents itself in different forms.

[0050] As a part of the anphibole and with the presence of magnesiumsilicatae, calcium and iron, are the crocidolite and the amosite.Belonging instead to the magnesium silicates is the chrysotile. Thesetypes of amiantus are more useful for their physical features whichpermit easy working.

[0051] Other types of amiantus are the actinolite, the anthophyllite andthe tremolite. The lowest common denominators or form of the differenttypes of amiantus is the presence of hydroxil groups in the form ofwater of hydration (H—O—H). With high temperatures the hydroxil grouppresents in the amiantus abandons the structure and almost contemporarythe calcined alumina losses at hot the hydroxil groups making availablethe valances of the aluminum. These amiantus products reacting with theoxides of the dehydroxyling minerals of the amiantus provide for theformation of minerals with different mineralogic structures, that is,minerals innocuous for the health as cited to the exit of thetransformation method.

[0052] Also the clay issues has the function to oxide bearer for thereaction at the solid state at hot and of sintering ligand. All theobtained materials are permanent mineral structures. For an example andfor test of the invented method are shown in sheets 1, 2, 3, 4 and 5,the chimic analysis X RF oxides with fusions make on the base of thereference set of rules and with x-ray diffractometer.

[0053] All of the illustrated tables are instead obtained with chemicalanalysis XRF eight oxides, with fusion, on the basis of rules POS011/00. It is to be noted that the tests confirm what was previouslycited. The material obtained by the present method is to be directlyused in the building or for the production of different articles.

[0054] The above cited example is given for the sole purpose toillustrate the invented method.

[0055] The realization forms are explanatory and not limitative of theinvented method. Each actuative form is to be considered inside themethod if technical equivalent on the base of the used substances. It isto point out that the fundamental feature of the method is to producebuilding material and articles economically advantageous, and it solvesthe problem of disposal of amiantus of waste with amiantus.

[0056] With respect to the drawings, these are just intended asproviding a pictorial representation of what is clearly set forth in thespecification, and may be omitted if necessary. Nevertheless, they areuseful to show the different components of waste products containingamiantus or formed completely of amiantus.

[0057] While there has been shown what is considered to be the presentlypreferred mode for carrying out the invention, various changes andmodifications may be made without departing from the scope of theinvention.

1. Transformation method of waste products containing or including all amiantus, comprising the steps of: adding to the waste product components selected from the group comprising calcined alumina, clay and materials having porosity like wood flour or hazel-shell flour at least once.
 2. The method as claimed in claim 1, comprising the following working phases: a grinding phase wherein the waste products are reduced to a dimension no greater than 0.063 millimeters; a dosing phase in which the different components are dosed and weighed; a mixing phase wherein the components are placed inside a mixer and addling nebulized water in a range of from 20 to 35% of the total of dry weight; an extrusion phase for realizing a plastic mass; a dimensioning phase to obtain a semi-manufactured product of desired dimensions; a drying phase for drying where the semi-manufactured product is dried to a temperature below 100° C.; a burning phase in which the manufactured products are passed inside of a furnace which is capable of reaching a temperature of 1250° C. to subject the product to a temperature up to 1250° C.; and an inspection phase and a final last phase of packaging/storing wherein the manufactured product, is free of amiantus, is packaging and stored so a completion of the working cycle.
 3. The method as claimed in claim 2, wherein the quantity percent of the waste product is of a quantity from 30% to 40% of the dried mixture, and including adding to this fixed quantity the refractory clay in a quantity percent comprising up to 30% of the weight, and sintering of the ligand and of oxides bearer for transforming the crystallographic structure of the waste product into a highly stable form formed to the oxides of the elements which form the same amiantus, whereas, in the mixing phase, the issue of a material of a given porosity results in a lightening of the structure.
 4. The method as claimed in claim 1, wherein the calcined alumina is added to the dosnig and to the mixing in a quantity percent ranging from 26% to 30% of the dried weight, such that the product is thinly divided and is extremely reactive so that the final goods are provided with good features of loading resistance and to the high temperatures.
 5. The method as claimed in claim 1, wherein the use of weight percentage of material of a given prosity is different if it is wood flour or hazel-shell flour is used.
 6. The method as claimed in claim 1 wherein hazel-shell flour is used.
 7. The method as claimed in claim 1, wherein the heating phase includes the following heating steps: for the first two hours the material is heated to a temperature of 350° C., for the next two hours and up to the fourth hour the material is heated to a temperature of 550° C., for the next two hours and up to the sixth hour, the material is heated to a temperature of 800° C., for the next three hours the temperature of 1050° C. is reached, and for another four hours of heating a temperature of 1200° C. is reached.
 8. The method according to claim 1 wherein the weight percentage of material having prosity is different if wood flour or hazel-shell flour is used.
 9. The method as claimed in claim 3, wherein the calcined alumina is added to the dosing phase and to the mixing in a quantity percent ranging from 26% to 30% of the dried weight, such that the product is thinly divided and is extremely reactive so that the final goods or manufactured product are provided with good features of loading resistance and to the high temperatures.
 10. The method as claimed in claim 9 wherein hazel-shell flour is used.
 11. The method as claimed in claim 10, wherein the heating phase includes the following heating steps: for the first two hours the material is heated to a temperature of 350° C., for the next two hours and up to the fourth hour the material is heated to a temperature of 550° C., for the next two hours and up to the sixth hour, the material is heated to a temperature of 800° C., for the next three hours the temperature of 1050° C. is reached, and for another four hours of heating a temperature of 1200° C. is reached.
 12. A method of transforming a waste product including amiantus or amiantus together with other undesired products or materials comprising: subjecting the waste product to several working phases; and adding of components such as calcined alumina, clay and materials having a porosity like wood flour or hazel-shell flour.
 13. The method according to claim 12, wherein said working phases include the following: a grinding phase in which the waste is reduced to a dimension no higher than 0.063 millimeters; a dosing phase in which different components are weighed; a mixing phase wherein the components are placed into mixer and nebulized water is added to a percentage of from 20 to 35% of the total of dry weight; an extrusion phase for producing a plastic mass; a drying phase during for drying the semi-manufactured product to a temperature not to exceed 100° C.; a burning phase where the manufactures of the waste products are passed inside furnaces to reach a temperature up to 1250° C.; and an inspection phase and a packaging/storing phase where the manufactured resultant waste product is free of amiantus and is packaged and stored to complete the working cycle.
 14. The method according to claim 12, wherein the quantity percent of the waste is of a value from 30% to 40% of the dried mixture, and including the step of adding refractory clay to bring the percentage of the refractory clay up to 30% of the weight, and sintering ligand and oxides bearer for transforming the crystallographic structure of the waste in a highly stable form to form the oxides of the elements which form the waste, and in the mixing phase, the issue of a material having porosity lightens the structure.
 15. The method as claimed in claim 14, wherein the calcined alumina is added to the dosing and to the mixing in a quantity percent of from 26% to 30% of the dried weight, in a thinly divided form to render it extremely reactive for permitting to have the final goods with features for resistance to loads and to the high temperatures.
 16. The method as claimed in claim 13, wherein the burning phase comprises the following steps during which the manufactured product is dried with a residual dampness up to 1% and passed through furnaces for heating up to a temperature of 1250° C., as follows: a. the product passes through a cooking cycle for two hours and is heated in a furnace to a temperature up to 350° C.; b. then the product is passed through a furnace and is heated up to a temperature of 550° C. for two hours; c. the product is then passed through a furnace and heated to a temperature of 800° C. for two hours; d. the product is then passed through a furnace and heated to a temperature of 1050° C. for three hours; e. the product is then passed through a furnace and heated to a temperature of 1180° C. for two hours; f. the product is then passed through a furnace and heated to a temperature of 1200° C. for four hours; and g. coating the product in a natural manner, and then sintering the product in a cooking phase.
 17. The method as claimed in claim 12, including adding the refractory clay in a quantity percent comprising up to 30% of the weight of the waste product, and sintering of the ligand and of oxides bearer for transforming the crystallographic structure of the waste product into a highly stable form formed to the oxides of the elements which form the same amiantus, to provide the waste product with a porosity which results in a lighter structure.
 18. The method as claimed in claim 17, including adding the calcined alumina in a quantity percent ranging from 26% to 30% of the dried weight, such that the product is thinly divided and is extremely reactive. 